CG13096

CG13096 encodes a 681-residue protein with a long disordered, lysine-rich N-terminal region (about residues 1-248), a central divergent ribosomal-protein-L1-like (uL1-like) alpha/beta domain, and an extremely acidic disordered C-terminal tail. It is not a ribosomal protein: the fly cytoplasmic uL1 proteins are RpL10Aa/RpL10Ab and the mitochondrial uL1m is mRpL1 (CG7494). By sequence similarity and most orthology resources it belongs to the eukaryotic lineage of nucleolar L1-domain ribosome-biogenesis factors that includes human RSL1D1 and yeast Utp30 and Cic1, although PANTHER separates it into a family of its own. Unpublished thesis work reports that the protein (there named Centagon 3) is nuclear and nucleolar in ovarian germ and follicle cells, binds RNA in vitro without clear sequence specificity, and is needed for normal germline development, but none of this has appeared in the peer-reviewed literature. Its molecular activity, RNA targets and role in ribosome biogenesis remain unestablished.